Fig. 3

Human macrophages survive in vivo for up to two weeks post-injection following injection directly into the circulation of the zebrafish. (a) Schematic showing experimental set up, where human macrophages were directly injected into the circulation of 2 days post-fertilization (dpf) larvae, after being differentiated from primary human monocytes. Injected larvae were imaged at 1, 7 and/or 14 days post injection (dpi). (b,c) Micrographs of whole larva at 3 dpf (left) showing distribution and survival of human primary macrophages (blue) differentiated at either at physiological temperature of zebrafish (28.5 °C) or at physiological temperature of humans (37 °C) before injection into the caudal vein of transgenic fli:GFP (vessels-red) zebrafish larvae. Micrographs display macrophage distribution at 1 dpi. Bottom panels: Micrographs of 3D projections at higher magnification of insets highlighted in tiled images showing distribution and survival of human primary macrophages (blue). (d) Top panel: micrograph shows tiled image of the 9 dpf zebrafish, 7dpi, showing distribution and survival of human primary macrophages differentiated at human physiological temperature (37 °C) (blue) injected into transgenic fli:GFP (vessels-red) zebrafish larva. Bottom panel: Micrographs of 3D projections at higher magnification of insets highlighted in tiled image showing distribution and survival of human primary macrophages (blue). (e) Top panel: micrograph shows representative tiled image of a 16 dpf zebrafish. Bottom panel: Micrographs of 3D projections showing distribution and survival of human primary macrophages (blue) at 14 dpi following injection to transgenic mpx:gfp (neutrophils-green)/flk:mCherry (vessels-red) zebrafish larvae at 2 dpf. Arrows indicate macrophage positions.